1. Field of the Invention
This disclosure is directed to a method of manipulating a spin state, and, more particularly, to a method of separating spin quantum states, in which, in a hybrid double quantum disk structure composed of a diluted magnetic semiconductor (DMS) and a ferroelectric compound semiconductor (FES), the polarization direction of the dipoles of the FES is switched.
2. Description of the Related Art
Although semiconductor integration techniques have advanced to the extent of enabling the integration of about five ten million transistors on one CPU (Central Processing Unit), computers having much higher capacity are still required in order to process tremendous quantities of information. However, it is impossible to continue to decrease the size of devices or the width of circuit lines in order to increase the degree of integration. Theoretically, lead wires having circuit line widths up to 4 nm are able to be realized, but, actually, even at a width of 16 nm, devices do not function due to excessive heat generation by tunneling or interference and leakage current.
Attributable to the above problems, limitations are imposed on techniques for continuously integrating devices based on binary bits. However, if the number of bits is increased, even with integration techniques at the current level, the capacity problem of devices is expected to be overcome. The method of increasing the number of bits includes the fabrication of multinary bit devices by using the spin degrees freedom of carriers (electrons or holes), which is called spintronics. One of the main requirements of spintronic nanodevices is to manipulate the spin state in a quantum structure on the nanometer scale.
DMS and FES materials, used for the structure and method according to the example embodiments, has been intensively studied due to their applicability to nonvolatile memory, piezoelectric actuators, sensors, and semiconductor spintronic devices, and furthermore, one-dimensional structures such as nanowires or nanorods have been recently studied successfully.